Lovely shot--and great choice for the challenge. My only suggestion would be perhaps a more shallow DOF, to bring more focus on the flamingo. Still, works very well.
fits the challenge well but not a very creative composition, maybe backing up and using the rule of thirds would have improved it some, also it looks slightly over exposed
Great contrasts of colors and shapes. I like how you chose to emphasize the subject here and filled up most of the frame with the flamingo. The detail and focus is excellent as well.
If I was being really picky I'd say I wish there was more detail in the feathers. It's really hard to photograph such a light color but maybe a different time of day would have improved the light a bit. Regardless it's a beautiful pic and a great example of balance. (Why DO they stand like that?) I like the backdrop of purple flowers. It's in my top ten for sure. Good job!